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3c09001917
In regalloc, a sparse map is preallocated for later use by spill-in-loop sinking. However, variables (spills) are added during register allocation before spill sinking, and a map query involving any of these new variables will index out of bounds in the map. To fix: 1) fix the queries to use s.orig[v.ID].ID instead, to ensure proper indexing. Note that s.orig will be nil for values that are not eligible for spilling (like memory and flags). 2) add a test. Fixes #15585. Change-Id: I8f2caa93b132a0f2a9161d2178320d5550583075 Reviewed-on: https://go-review.googlesource.com/22911 Reviewed-by: Keith Randall <khr@golang.org> Run-TryBot: David Chase <drchase@google.com> TryBot-Result: Gobot Gobot <gobot@golang.org>
46 lines
829 B
Go
46 lines
829 B
Go
// compile
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// Copyright 2016 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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package bug
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func example(n int) (rc int) {
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var cc, ll, pp, rr [27]int
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for q0 := 0; q0 < n-2; q0++ {
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for q1 := q0 + 2; q1 < n; q1++ {
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var c, d, l, p, r int
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b0 := 1 << uint(q0)
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b1 := 1 << uint(q1)
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l = ((b0 << 1) | b1) << 1
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c = b0 | b1 | (-1 << uint(n))
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r = ((b0 >> 1) | b1) >> 1
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E:
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if c != -1 {
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p = ^(l | c | r)
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} else {
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rc++
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goto R
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}
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L:
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if p != 0 {
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lsb := p & -p
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p &^= lsb
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ll[d], cc[d], rr[d], pp[d] = l, c, r, p
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l, c, r = (l|lsb)<<1, c|lsb, (r|lsb)>>1
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d++
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goto E
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}
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R:
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d--
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if d >= 0 {
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l, c, r, p = ll[d], cc[d], rr[d], pp[d]
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goto L
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}
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}
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}
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rc <<= 1
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return
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}
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